Hereditary angioedema (HAE) is a disorder that causes repeated attacks of painful swelling. The swelling most often affects the skin, digestive tract, and upper airway (tongue, throat, and larynx).
“Angioedema” is the medical term for swelling. “Hereditary” means the condition runs in the family.
HAE is rare. An estimated 1 in 10,000 to 1 in 150,000 people worldwide have this condition.
The most common form of hereditary angioedema is caused by a change to a gene that makes C1 inhibitor (C1-INH). This blood protein regulates the flow of fluids in and out of cells.
When you do not have enough C1-INH or your C1-INH doesn’t work as it should, it causes fluid to leak out of blood vessels and build up under your skin.
This causes your hands, feet, arms, legs, throat, or face to quickly swell. Sometimes, more than one area may be affected at once.
A few different medicines can help you manage HAE symptoms. A healthcare professional will give you advice on how to prevent attacks and feel better overall. Here are a few questions you might want to ask during your next visit.
HAE causes sudden attacks that involve painful swelling. How often these attacks happen, which areas of the body they affect, and how severe they are differs for each person.
Some people rarely have attacks. Others have symptoms a few times per week.
Untreated attacks usually come on over a period of several hours and last for
- You feel very tired.
- Your skin tingles.
- Your voice gets hoarse before the swelling starts.
The main symptom of HAE is hard and painful swelling under the skin. It most often occurs in the:
Specific symptoms depend on which area of your body the attack affects:
- Skin: painful swelling (not red or itchy); very few people have a rash
- Gastrointestinal (GI) tract: abdominal pain, nausea, vomiting, diarrhea
- Throat and airway: sore throat, trouble swallowing, trouble speaking, difficulty breathing
Swelling in the throat and airway is the most serious symptom. If your airway closes, you may not be able to breathe. That’s why it’s important to get treated right away when your symptoms start.
HAE attacks can be unpredictable. They may be linked to certain triggers, which vary for each person.
The most common triggers are:
- stress and anxiety
- dental procedures
- infections like a cold or the flu
- hormone levels, including fluctuations during menstruation and pregnancy
- medications such as birth control pills, hormone therapy, and some blood pressure drugs
- physical exertion from activities like raking or pushing a lawn mower
One way to learn your triggers is by keeping a symptom diary. Write down each symptom and what you were doing when it started. Share this diary with your doctor during visits.
HAE is a complex condition that affects many different parts of your body. Your primary care doctor may be able to manage some of your care. You may also see one or more of these specialists:
- allergist or immunologist
- obstetrician/gynecologist (OB-GYN)
- genetic counselor
Look for doctors who have experience treating HAE. Organizations like the US Hereditary Angioedema Association can help you find specialists in your area.
HAE attacks come on quickly, and they can be unpredictable. Suddenly, your hands, feet, face, belly, or throat swell up. These painful attacks can make it hard for you to work or go to school. You may not be able to participate in your usual sports or social activities.
Knowledge is power when you live with HAE. Once you know your triggers, you can take steps to avoid them. For example, you might:
- Practice relaxation exercises to de-stress.
- Go to bed earlier to make sure you sleep enough.
- Ask your doctor to change or take you off any medications that make your symptoms worse.
- Get help with chores that require a lot of physical effort, like mowing the lawn.
Treatments can help prevent HAE attacks from occurring. Some medications replace the C1-INH protein your body is missing. Others block a substance called bradykinin that causes swelling during HAE attacks.
Medications approved by the Food and Drug Administration (FDA) to prevent HAE attacks include:
- lanadelumab (Takhzyro)
- plasma-derived nanofiltered C1-INH (Cinryze, Haegarda)
- berotralstat (Orladeyo)
Other preventive treatments that are not FDA-approved for HAE but are sometimes prescribed by doctors include:
- danazol (Danocrine)
- stanozolol (Winstrol)
Most HAE medications come as an injection or IV that you give yourself. Orladeyo is the only oral drug for HAE.
You can take a preventive medication for a short time before a stressful event or other situation that would typically trigger your symptoms. Or you can take medication regularly to prevent attacks over the long term.
Another group of medications stop attacks when they happen. It’s important to have one of these medications with you all the time, so you can take it quickly when an attack starts.
- ecallantide (Kalbitor)
- icatibant (Firazyr)
- plasma-derived nanofiltered C1-INH (Berinert)
- recombinant human C1-INH (Ruconest)
You can give yourself all these of medications except Kalbitor, which a doctor must administer.
The gene change that causes HAE can pass from parents to their children. And only one parent needs to pass on the gene to their child for the disease to appear.
However, just because you have this condition doesn’t mean you will give it to your kids. Each of your children has about a 50/50 chance of inheriting the gene from you.
If you’re concerned about your children having HAE, talk with your doctor or a genetic counselor. They can walk you through your risks and options.
Hereditary angioedema causes painful swelling in the skin and mucous membranes. Your symptoms can appear without warning. The severity and unpredictability of this disease can have a big impact on your day-to-day life.
Your doctor can help you manage your condition. Medications can help prevent attacks and stop them when do they happen. Lifestyle changes can also help you avoid triggers that cause your symptoms.